Fixing a MacBook Pro that doesn't turn on

October 11, 2019

What's wrong with this MacBook?

This customer sent in their MacBook Pro to our store in New York City for our logic board repair service because it wasn't turning on. The customer had attempted to replace their own keyboard and clean off their motherboard.

How do we fix this issue?

Initial Diagnosis

First, we start off by plugging in a known good DC-In board. We still get no power on the board. Next, we measure the main power rails on the machine, starting with PP3V42_G3H and PPBUS_G3H. PP3V42_G3H gives us 3.42V as it should, and PPBUS_G3H has 0.02V. Next, we measure SMC_BC_ACOK, which is one of the rails required to get a green light on the charger. SMC_BC_ACOK has 0.00V. This rail comes from the U7000 charging IC. After measuring the resistors around the chip, we find that the chip is pulling the lines on R7010 and R7011 to ground.

Repairing the board

With our hot air rework station, we remove the U7000 chip, which is an ISL6259 IC. Next, we tin the pads under this QFN chip, get ourselves a new ISL6259, and replace it. After letting the board cool down, we have fanspin and power to the board.

I can't fix this myself. How do I get it fixed?

Rossmann Repair Group repairs MacBooks in New York City. Our MacBook Repair is not limited to Austin though, we accept mail-in repairs from virtually anywhere! Visit https://sendyourmacbook.com to start your MacBook repair.

 

 

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